around this issue Docs are being improved for this. Look at the current staging docs for DataGrid near the bottom where it says "See Also" the link for "Demos on how to display and edit date value in grid cells"
HTML5 TextBox Type=date causes reformatting of date string?
around this issue I am trying to sort date in the dojo grid. But the sorting is not happening properly, it considers date as string and sorting doesn't work. Is there anyway that would help me? , As your date format is